Stormwater runoff is a liquid highway that washes pollutants off the land and into local waterways. Hard surfaces such as roads, rooftops and parking lots speed the highway along until it reaches streams and rivers with a volume that erodes shorelines and leaves the water thick with sediment.

It's a major problem in urban areas, and a growing concern in the Chesapeake Bay region, where development is quickly changing green terrain to gray.

To help protect the Bay and other waterbodies, the U.S. Navy has launched a new policy aimed at preventing an increased volume of stormwater runoff from many of its properties nationwide, even as new development takes place.

"When we put in a new road or building or make major renovations to existing structures, we will look at the stormwater coming off that property and design a new system so that the same or less stormwater, nutrients and sediment come off the property when the construction is finished," said Donald Schregardus, deputy assistant secretary of the Navy for the Environment.

The policy requires the use of low impact development techniques to control runoff from all new construction and large renovations on Navy property beginning in 2011.

Specially designed landscape features, such as planted swales and bio-retention areas, will be placed at strategic locations to capture rainwater where it can be absorbed or evaporated on site. Rain barrels will store water and release it slowly. Pervious pavers will allow water to pass through some walking and parking areas and soak into the ground.

"It's an important step that will get people thinking in a new direction," Schregardus said. "We've had tremendous success with low impact development at some individual sites and now it will be a part of how we do business."

The Naval Medical Center in Portsmouth, VA, was recognized by the Elizabeth River Project for its use of nearly 38,000 square feet of pervious pavers that reduced traditional paved surfaces by 10 percent. Foundation planters, swales and bio-retention areas absorb stormwater at the U.S. Naval Observatory, Washington Navy Yard, and Naval Station Norfolk.

Schregardus said the new policy will force people to look at the life cycle cost of stormwater treatment. When stormwater degrades or erodes a stream, the restoration costs can be huge.

"Short-term solutions only put a bigger price tag out there and push it into the future," Schregardus said. "The Navy is attempting to lower the long-term cost for cleaning up the Bay and for meeting our Clean Water Act responsibilities."

The nationwide policy stemmed from concerns about the impact of the Base Realignment and Closure Process process on the Chesapeake Bay. BRAC -a massive federal effort to distribute military bases more efficiently-is expected to create thousands of jobs in the Bay region by 2011. Maryland expects between 40,000 to 60,000 new military and contractor jobs in an eight-county area. In Virginia's part of the watershed, roughly 9,400 jobs will be created in or shift between Navy and Marine Corps installations.

BRAC is expected to have a resounding effect on land use, transportation, tax revenue, schools and the housing market in Maryland and Virginia, with ripple effects in neighboring states. Development will increase both on military property and in surrounding communities.

"We recognize the potential impact of this transition on the Chesapeake Bay," Shregardus said. "BRAC has reduced our nationwide footprint but several of the installations in the Bay region are substantially growing, increasing activities, people, soldiers, sailors and Marines."

Schregardus said that discussions of BRAC among federal agencies helped to put the Navy's interest in LID policies on a fast track.

"The Department of the Navy, as well as other federal agencies, committed in 2000 to do all they could by 2010 to help achieve the water quality goals of the Chesapeake Bay," Schregardus said. "Basically, we want to be a good neighbor."

The new stormwater policy applies only to Navy property. State and local policies, as well as voluntary interest by developers, will determine whether similar techniques are used on private developments that arise in response to BRAC.

Efforts are under way to develop similar low impact development policies for the U.S. Army, Air Force and Defense Logistics Agency.

"The Department of Defense is probably the largest single landowner in the Chesapeake Bay, with more than 400,000 acres of land and significant miles of shoreline," Schregardus said. "We recognize that we need to play an active role in meeting the goals for the Bay."